Blood pressure bag or similar article



cs. WINDER 2,335,204

BLOOD PRESSURE BAG OR SIMILAR ARTICLE Nov. 23, 1943.

2 Sheets-Sheet 1 Original Filed Aug. 17, 1940 ill Nov. 23, 1943. s. L. WINDER BLOOD PRESSURE BAG OR SIMILAR ARTICLE Original Filed Au 1'7, 1940 2 Sheets-Sheet 2 Patented Nov. 23, 1943 BLOOD PRESSURE BAG OR SIMILAR ARTICLE George L. Winder, Cuyahoga Falls, Ohio, assignor to American Anode Inc., Akron, Ohio, a corporation .of Delaware Original application August 17, 1940, Serial No. 353,145. Divided and this application May 29, 1942, Serial No. 445,079

5 Claims. (01. 128-327) This invention relates to hollow rubber articles provided with communicating tubes extending therefrom and especially to blood pressure bags embodying novel constructional features and to economical and efficient procedure for manufacturing such articles. The invention will be described in detail with reference to the accompanying drawings of which:

Fig. 1 is a sectional elevation illustrating a preliminary step in the manufacture of a tube assembly employed in the present invention and showing an auxiliary deposition form immersed in a liquid rubber composition for receiving a coating of rubber.

Fig. 2 is a perspective view illustrating a further step in the process and showing the tube assembly being removed from the auxiliary deposition form.

Fig. 3 is a sectional elevation illustrating a further step in the process and showing'the tube assembly associated with aprincipal deposition form and the composite assembly immersed in a liquid rubber composition for receiving a coating of rubber.

Fig. 4 is a perspective view showing the composite assembly of Fig. 3 with a rubber coating thereon and further illustrating the step of slitting a portion of the coating to permit removal of the principal form. 1

Fig. 5 is an elevation illustrating the step of removing the rubber coating from the principal deposition form.

Fig. 6 is a perspective view, partially broken away and sectioned for clarity of illustration, showing the coating after removal from the principal form and further illustrating a preliminary step in sealing the slit in the coating.

Fig. 7 is a sectional elevation illustrating a further step in sealing the slit and showing an end portion of the coating immersed in a liquid rubber composition. 1

Fig. 8 is a perspective view showing a finished blood pressure bag made in accordance with the present invention.

Fig. 9 is a vertical section taken on'line. 9.-9 of Fig.5.

Fig. 10 is a fragmentary elevation, broken away and sectioned, showing an end portion of a blood pressure bag embodying a modification of the invention in which a reinforcing element is included in the region of the slit.

Equipment used by physicians for determining the blood pressure of patients includes a unit known in the art as a blood pressureb'ag. Such blood pressure bags customarily ar made of rubber or analogous material and include a gen-'- erally rectangular flat hollow bag B and a pair of communicating tubes T, T extending from one of the longer edges of the bag at a position adjacent one end thereof as indicated in Fig. 8. According to the present invention, such a blood pressure bag is made by a process in which a tube assembly is first formed independently, after which the bag portion is formed in contiguous cohering relation with a portion of the tube assembly.

To form the tube assembly, I utilize an auxiliary deposition form indicated generally by the numeral 10. The auxiliary form l0 includes arelatively small trapezoidal plate member ll provided with two rod-like stems [2, I2 extending from one edge of the plate member I l in the plane of the plate, the stems 12 corresponding in size and length to the interior diameter and length of the tubes desired in the blood pressure bag. The form l0 may have a supporting member such s the hook [3 extending from the opposite edge of the plate. To produce the tube assembly, the auxiliary form Ill is coated with rubber as by immersing the form in a liquid rubber composition such as any suitably compounded latex L as illustrated in Fig. 1. Desirably the form I U is pre-- coated with a composition adapted to coagulate latex composition as described in U. S. Patent No. 1,908,719, and such coagulant composition desirably should contain a powdery separating material as described in U. S. Patent No. 1,924,214. The form In is completely immersed in the latex as shown in Fig. l and is permitted to remain therein until a rubber deposit from .015 to .025" thick (when finished) has been deposited over the entire form. The form then desirably is raised until the liquid level of th latex is just below the edge of the plate member I l and deposition on the immersed stems I2 is then continued until the total rubber deposit on the stems is from .030 to .060" thick (when finished). Such continued deposition may be effected by progressive action of coagulant initially applied to the form, or the stems l2 may be re-dipped a number of times, either with or without intermediate 00- agulant treatments, to build up the desired thickness of rubber. The form l9 together with the deposited rubber coating is then removed from the latex and the rubber deposit is dried but not vulcanized. The rubber coating is then slit around the top edge of the plate I l to permit removing the tube assembly from the form as shown in Fig. 2, after which the ends of the tubes are opened by cutting off the closed ends as indicated at 24, 24.

It will be appreciated that the tube assembly so produced comprises a pair of relatively long rubber tubes M, M which terminate in a flaring, flange-like member l5 comprising two generally parallel flaps. As will appear more clearly later, the flaring member I5 will constitute a reinforcing element in the finished bag. To insure a neat product, the exposed end of the element I15 desirably should be trimmed smoothly as along the semi-circular dotted line shown in Fig. 2 and indicated by the numeral l5.

I then provide a principal deposition form including a main portion 81 of generally flat rectangular configuration adapted to form the bag portion of the final product. The principal form also is provided with two rod-like stems l3, l8 which extend outwardly in the plane of the form from one of the longer edges of the main portion IT at a position adjacent one end thereof as shown in Fig. 3. The stems l8 desirably should be somewhat longer than the rubber tubes !4 of "the prepared tube assembly, but otherwise should correspond in size to the tubes.

7 I next place the prepared tube assembly on the principal form by sliding the tubes it down over the stems l8 until the flaring flange or reinforcing element I 5 embraces closely the portion of the main form adjacent the bases of the stems I 8 as may be seen more clearly in Fig. 3. Desirably the underside of the reinforcing element I5 is cemented to the form I! by means of a thin coating of rubber cement or other suitable adhesive which will prevent seepage of liouid rubber composition between the two members durin subsequent operations while permitting ready removal of'the com leted article includin the element l5. A suitable su porting clamp I9 is then priate coa u ant for latex. The assembly with its over-all coating of rubber is then removed from the latex and. the rubber is dried, but not vulcanized; I 7

To permit removal of the principal form. I then slit a portion of the rubber deposit 25, preferably along the maior len th of the shorter edge of the de osit removed from the tube assembly. Such. slitting-conveniently may be accomplished simply byxpro ressively pressing a heated cutting element 20 or other suitable instrument against the rubber along the edge (Fig. The principal form is then removed tln'ough the opening made by the slit by doubling the rubber coating back over the form as shown in Fig. 5, and stripping the tubes from the stems. To seal the opening made by the slit, the cut edges at the slit preferably are coated with rubber cement or other rubber adhesive as indicated at.

rubber 22 isproduced thereover as by immersing the end portion, for example about one inch, of

the bag in latexL or other liquid rubber composition as shown in Fig. '7. This procedure may be repeated several times to build up a rubber cap of any desired thickness.

It is also possible to utilize a coagulant to produce a heavier cap with a lesser number of dips and the coagulant may be applied to the entire area to be capped or to a desired restricted portion thereof. In the latter case, the cap will be thicker over the area to which coagulant was applied.

Finally, the entire article is thoroughly dried and vulcanized by heating in the usual manner to produce a finished blood pressure bag as shown in Fig. 8. T 7 V For further reinforcing the seal at the slit, when desired, a strip of textile fabric 23 (Fig. 10) or otherreinforcing material may be placed over the slit prior to application of the rubber cap 22, or the fabric strip may be interposed between any of the successive deposits constituting the cap 22. In either case, the fabric 23 preferably is pretreated with latex or other rubber composition to secure more perfect anchorage in the rubber.

It will be appreciated from the foregoing that a blood pressure bag or other article produced according to the present invention includes a hollow bag portion B with two communicating tubes T, T, extending therefrom and that the reinforcing element i5 is attached to the interior face of the wall 25 of the bag and is continuous with the innor portion I 4 of the tubes T, as more clearly shown in Fig. 9. The outer portions of the tubes T are continuous with the wall 25 of the bag B so that an unusually strong and essentially unitary-structure is produced which effectively resists failure heretofore experienced at the junction between the tubes and the bag. Furthermore, the products of the present invention include a reinforcing cap over the slit at the end of the bagwhich insures effective sealing and reinforcement against failure upon inflation. The cap also serves to provide a balanced appearance. It will further beappreciated that the constituent parts of the articles cohere and form an essentially unitary struc-ture, although the several individual parts may still be identified in the finished product.

The term rubber has been used in a generic sense to include not only natural Hevea rubber but also all analogous natural and synthetic rubbers and rubber-like materials.

Whilethe invention has been described in considerable detail in connection with the manufacture of'blood pressure bags, the principles herein set'o'ut obviously may be applied with advantage in the manufacture of numerous other articles.

It will likewise. be understoodthat many modifications and variations in details of the procedure and materials described may be effected without departing from the spirit and scope of the invention as defined by the appended claims.

This application is a division of my copending application, Serial No. 353,145, filed August 1'7, 1940; now U. S. Patent No. 2,313,792, granted March 16, 1943. i

I claim:

1. An article of manufacture formed of rubber and comprising a hollow bag portion, a com 'municating tube extending therefrom, and a reinforcing elernent attached tothe interior wall of the bag portion in the region about the tube, the inner portion of the tube wall being continuous with the said reinforcing element and the outer Portion 'ofthe tube wall being continuous with the wall of the said bag portion, the constituent parts of the article being cohered to form an essentially unitary structure.

2. A medical accessory unit formed of rubber and comprising a hollow bag portion, a communicating tube extending from the bag portion, a reinforcing element attached to the interior Wall of the bag portion in the region about the tube, said reinforcing element being a continuation of the structure of the tube, and a reinforcing cap covering an edge portion of the bag substantially spaced from the tube, the constituent parts of the article being cohered to form an essentially unitary structure.

3. A blood pressure bag or similar article formed of rubber and comprising a hollow bag portion of generally rectangular flat configuration, a plurality of communicating tubes extending from the bag portion at a position adjacent one end thereof, and a reinforcing element attached to the interior wall of the bag portion in the region about the tubes, said reinforcing element being a continuation of the structure of the tubes.

4. A blood pressure bag or similar article formed of rubber and comprising a hollow bag portion of generally rectangular fiat configuration, communicating tubes extending from the bag portion at a position adjacent one end thereof, a reinforcing element attached to the interior wall of the bag portion in the region about the tubes, said reinforcing element being a continuation of the structure of the tubes, and a reinforcing cap covering the end of the bag portion removed from the tubes, the constituent parts of the article being cohered to form an essentially unitary structure.

5. An article of manufacture formed of rubber and comprising a hollow bag portion, a communicating tube extending outwardly therefrom, and a reinforcing element attached to the Wall of the bag portion in the region about the end of the tube, the wall of said tube comprising two distinct concentric wall portions, one of said wall portions being continuous with the said reinforcing element and the other of said wall portions being continuous with the Wall of the said bag portion, all the aforesaid portions presenting the continuous, grainless rubber structure characteristic of rubber deposited in situ from latex and all the portions which are in contigous relation being cohered to form an essentially unitary structure.

GEORGE L. WINDER. 

